7 mm Tag offers a nylon sheath and core. Out of the three lines offered, this rope falls perfectly in the middle for elongation and weight. There are times when you only want to carry a single rope on a climb, but if the rappels are long, having a second rope makes a full length rappel possible. Using tag lines is a technique for advanced climbers and takes proper training on how to safely use them.
Tag lines are not to be used for lead climbing. Tag lines should never be used in place of a dynamic rope, and caution should always be taken when rappelling with two different diameter ropes.